The use of internal floating pistons, —also known as and will be referred to herein as IFPs—in damping cylinders to compensate for volume changes due to the displacement of damping fluid within the damping cylinder and thermal expansion of the damping fluid, is well known. For example, the following Fox Racing Shox (Fox Factory, Inc.) patents depict the use of an IFP: U.S. Pat. No. 6,135,434; U.S. Pat. No. 6,296,092; U.S. Pat. No. 6,311,962; U.S. Pat. No. 6,360,857; U.S. Pat. No. 6,415,895; and U.S. Pat. No. 6,604,751 and are incorporated by reference herein as are all the patents and published patent applications referred to within this patent application.
Furthermore, it is often common to have shafts extending the longitudinal length of the damping cylinder. The shaft may comprise a piston rod, a valve control rod, or a combination of both. For example, in FOX U.S. Pat. No. 6,360,857, we depict the use of a shaft extending the length of the damping cylinder wherein the shaft comprises a piston shaft and a control shaft. In another FOX patent, the shaft passes through the IFP. See U.S. Pat. No. 6,415,895 (FIG. 7).
The present invention is an extremely simple to implement improvement and innovation in damping cylinders, and especially those damping cylinders that may have originally been designed to have both IFPs and shafts or in any other damping cylinder.